Stock J, Da Re S
Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
Cell Calcium. 1999 Nov;26(5):157-64. doi: 10.1054/ceca.1999.0075.
The mechanism of stimulus-response coupling in bacterial chemotaxis has emerged as a paradigm for understanding general features of intracellular signal transduction both in bacterial and eukaryotic cells. Until recently it was thought that the mechanism involved reversible stochastic interactions between dimeric receptors freely diffusing in the cytoplasmic membrane and several soluble signal transduction proteins within the cytoplasm. Recent results have shown that this view is an oversimplification. The receptors and most of the signal transduction proteins are organized together in a higher ordered structure at one pole of the bacterial cell. The scaffolding network within this structure appears to be composed of C-terminal alpha-helical extensions of the membrane chemoreceptor proteins held together in a lattice by tandem SH3-like domains. Results suggest that stimuli are detected through the perturbations they induce in scaffolding architecture.
细菌趋化作用中刺激-反应偶联机制已成为理解细菌和真核细胞内细胞信号转导一般特征的范例。直到最近，人们还认为该机制涉及在细胞质膜中自由扩散的二聚体受体与细胞质内几种可溶性信号转导蛋白之间的可逆随机相互作用。最近的结果表明，这种观点过于简单化了。受体和大多数信号转导蛋白在细菌细胞的一极以更高阶的结构组织在一起。该结构内的支架网络似乎由膜化学感受器蛋白的C末端α-螺旋延伸组成，这些延伸通过串联的类SH3结构域以晶格形式结合在一起。结果表明，刺激是通过它们在支架结构中引起的扰动来检测的。
